FLORIDA GEOLOGICAL SURVEY. 
FIFTH ANNUAL REPORT. PL. 3. 
Fig. 1.—Sample of phosphate illustrating the formation of phosphate by the 
replacement process. The rock was clearly originally limestone of the Vicksburg 
formation, the form of the shells being well preserved. The carbonate has been 
replaced by phosphate, and the rock as shown by analysis is now a high grade 
phosphate. Natural size. 
Fig. 2.—Piece of phosphate rock showing secondary deposition in cavities and 
recementation of broken fragments. Collection of H. Bystra. Natural size. 
